Math
posted by Yakima .
A chemist needs to mix an 18% acid solution with a 45% acid solution to obtain a 12 liter mixture consisting of 36% acid. How many liters of each acid solutions must be used?

amount of 18% solution  x L
amount of 45% solution  12x L
.18x + .45(12x) = .36(12)
times 100
18x + 45(12x) = 36(12)
take it from here